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Key species act as warning signs of ecosystem collapse
The Earth’s biodiversity is under attack. We would need to travel back over 65 million years to find rates of species loss as high as we are witnessing today. Conservation often focuses on the big, enigmatic animals – tigers, polar bears, whales. There are many reasons to want to save these species from extinction. But what about the vast majority of life that we barely notice? The bugs and grubs that can appear or vanish from ecosystems without any apparent impact? Biodiversity increases resilience: more species means each individual species is better able to withstand impacts. Think of decreasing biodiversity as popping out rivets from an aircraft. A few missing rivets here or there will not cause too much harm. But continuing to remove them threatens a collapse in ecosystem functioning. Forests give way to desert. Coral reefs bleach and then die.
Wolves Reshape Ecosystem
In 1995, the US Fish and Wildlife Service, along with Canadian biologists, captured 14 wolves in Canada and placed them in Yellowstone National Park, where they had been extinct since 1926. Over the next few years, the number of wolves rose, but that was the least of the changes that took place in Yellowstone.
